1. Field of Invention
The present invention relates to combustion fuels. In particular, it relates to a fuel additive composition.
2. Description of Related Art
Numerous combustion fuels are known. Combustion or burning is a complex sequence of exothermic chemical reactions between a fuel and an oxidant accompanied by the production of heat or both heat and light in the form of either a glow or flames. Direct combustion by atmospheric oxygen is a reaction mediated by radical intermediates. The conditions for radical production are naturally produced by thermal runaway, where the heat generated by combustion is necessary to maintain the high temperature necessary for radical production
In a complete combustion reaction, a compound reacts with an oxidizing element, such as oxygen or air, and the products are compounds of each element in the fuel with the oxidizing element. For example:CH4+2O2→CO2+2H2O
In the large majority of the real world uses of combustion, the oxygen (O2) oxidant is obtained from the ambient air and the resultant flue gas form the combustion will contain nitrogen:CH4+2O2+7.52N2→CO2+2H2O+7.52N2+heat
As can be seen, when air is the source of the oxygen, nitrogen is by far the largest part of the resultant flue gas.
Traditional combustion processes are never perfect or complete. In flue gases from combustion of carbon (as in coal combustion) or carbon compounds (as in combustion of hydrocarbons, wood, etc.) both unburned carbon (as soot) and carbon compounds (CO and others) will be present. Also, when air is the oxidant, some nitrogen will be oxidized to various nitrogen oxides (NOx).
Rapid combustion is a form of combustion in which large amounts of heat and light energy are released, which often results in a fire. This is used in a form of machinery such as internal combustion engines and in turbines. Sometimes, a large volume of gas is liberated in combustion besides the production of heat and light. The sudden evolution of large quantities of gas creates excessive pressure that produces a loud noise known as an explosion.
In complete combustion, the reactant will burn in oxygen, producing a limited number of products. When a hydrocarbon or any carbon based fuel burns in air, the combustion products will also include nitrogen. Complete combustion is the goal, but almost impossible to achieve.
Turbulent combustion is a combustion characterized by turbulent flows. It is the most used for industrial application (e.g. gas turbines, diesel engines, etc.) because the turbulence helps the mixing process between the fuel and oxidizer.
Combustion of a liquid fuel in an oxidizing atmosphere actually happens in the gas phase. It is the vapor that burns, not the liquid. Therefore, a liquid will normally catch fire only above a certain temperature, its flash point. The flash point of a liquid fuel is the lowest temperature at which it can form an ignitable mix with air. It is also the minimum temperature at which there is enough evaporated fuel in the air to start combustion.
The act of combustion of solid fuels consists of three relatively distinct but overlapping phases:
Preheating phase, when the unburned fuel is heated up to its flash point and then at the fire point flammable gases start being evolved in a process similar to dry distillation.
Distillation phase or gaseous phase, when the mix of evolved flammable gases with oxygen is ignited. Energy is produced in the form of heat and light. Flames are often visible. Heat transfer from the combustion to the solid maintains the evolution of flammable vapors.
Charcoal phase or solid phase, when the output of flammable gases from the material is too low for persistent presence of flame and the charred fuel does into burn rapidly anymore but just glows and later only smolders.
To improve combustion, various additives and catalysts have been developed. These typically vary based on the type of fuel, and whether it is a solid or liquid. For example, chemical compositions are added to fuels and lubricants to control the physical and chemical properties of the fuel to improve engine performance. For example, Shields, U.S. Pat. No. 4,340,804, issued Dec. 23, 1980 discloses an additive for hydrocarbon fuels, which are the reaction products of a polyamine and an alkyl ester of acrylic or alkyl acrylic acid particularly suitable for gasoline to reduce the deposition of carbon and other materials in the combustion areas of the engine.
Fuel Cells
Another type of fuel is employed with fuel cells, which extract chemical energy from a mixture to create electricity. A fuel cell creates electricity directly from the energy in chemical fuels without an intermediate conversion into thermal energy. It works similar to a battery. In a battery there are two electrodes separated by an electrolyte. At lease one of the electrodes is generally made of a solid metal, which is converted into another chemical compound during the production of electricity. The electrical energy that a batter can produce in one cycle is limited by the amount of solid metal that can be converted. Conversely, in a fuel cell the solid metal electrodes are replaced by an electrode that is not consumed and a fuel high in ionic radical species that continuously replenishes the fuel cell. This fuel reacts with an oxidant such as oxygen from the other electrode. A fuel cell produces electricity as long as more fuel and oxidant are pumped through it. A typical fuel cell thus reacts oxygen with a fuel to produce electricity and fuel oxide byproducts. The basic core of the fuel cell consists of manifolds, an anode, a cathode, and electrolyte generally called the stack.
Of particular use with the present fuel composition are direct alcohol fuel cells, which have an operated temperature of between 50-100° C., and are particularly suited for powering portable and mobile devices from fuels have many OH groups. Heretofore, these fuel cells typically combine air with alcohol to produce electricity and CO2 byproducts.
Additives
Born et al., U.S. Pat. No. 4,347,062 issued Aug. 31, 1982 discloses a combustion improving additive for liquid fuel consisting essentially of an iron complex soluble in organic media, formed by reacting a sulfonic acid with ferric hydroxide in such proportions as to obtain a ratio of the number of acid gram-equivalents of the sulfonic acid to the number of gram-atoms of the iron in the range from ⅙ to 1/12. The reaction is conducted in the presence of a light aromatic hydrocarbon or a light halogenated aliphatic hydrocarbon having a boiling point from 80 degrees to 230 degree C., and an organic liquid containing oxygen, at least partially miscible with water and substantially miscible with hydrocarbons to produce the iron complex. The iron complex provides a combustion adjuvant for liquid fuels to save energy and reduce pollution.
Brennan et al., U.S. Pat. No. 7,300,477 issued Nov. 27, 2007 discloses another method and fuel additive including iron containing compounds for protecting and improving the operation of diesel fuel combustion systems.
Van den Neste et al., U.S. Pat. No. 6,096,104 issued Aug. 1, 2000 discloses a composition including at least three metals (M1, M2, M3) where the weight ratio of the metal (M3) to metal (M2) is greater than 0.15. The first metal (M1) is selected from the iron group or the manganese group (preferably iron, manganese, cobalt and nickel). The second metal (M2) is selected from the rare earth group (preferably cerium, lanthanum, neodymium and praseodymium). The third metal (M3) is selected from the alkaline or alkaline-earth metal group (preferably barium strontium, calcium and lithium). These mixed organometallic compositions are used as additives to hydrocarbonic liquid fuels to improve combustion. These additives have metallic oxides, which adsorb on asphaltenes and because of their catalytic effect on these asphaltenes they reduce the quantity of solid unburned components released during combustion.
Dodd et al., U.S. Pat. No. 6,663,680 issued Dec. 16, 2003 discloses a fuel which is a hydrocarbon oil-in-water emulsion for gas turbines, which minimizes corrosion of turbine blades by keeping the sodium ion content of the emulsion to less than 1 ppm.
Miyawaki et al., U.S. Pat. No. 4,968,322 issued Nov. 6, 1990 discloses a fuel oil additive with at least two kinds of soaps selected from cerium, neodymium and lanthanum, which are added as combustion promoters for heavy oil, coal slurries, or COM.
Cited for general interest is Michelfelder et al., U.S. Pat. No. 4,461,224 issued Jul. 24, 1984 providing a method of minimizing the emission of contaminants from flame combustion via additives added to the combustion chamber by means of a gaseous and/or liquid carrier flow accompanied by the formation of a veil which surrounds the burner flame. Additional additives are then reacted outside of the combustion chamber.
Despite the wide variety of additives available for fuel applications, there still remains a need for improved additives to provide increased deposit control and more efficient burning.
Catalysts
Haskew, U.S. Pat. No. 6,776,606, issued Aug. 17, 2004, is a recent example of a catalyst composition and method for oxidizing fuels. The catalyst composition comprises at least one compound having one of a group III, group IIA or Lanthanide element such as, for example, Aluminum, Magnesium or Cesium, and at least one compound having at least one element selected from group IA, group IVA, group VI, group VII, group VIII, group IB, group IIB, and combinations thereof, such as, for example platinum, rhodium and rhenium. It thus provides a method for oxidizing a fuel, the method comprising providing a fuel and a catalyst mixture; transporting the fuel and the catalyst to the flame zone separately; mixing the fuel and the catalyst; and oxidizing the fuel. The method and catalyst mixture may be used for oxidation of any hydrocarbon based fuel. Improved results from the use of the group III, group IIA or Lanthanide group elements include increase power, reduced harmful emissions, and smoother oxidation process.
Catalysts are expensive, and often require complex apparatus for proper combustion enhancement.
The fuel additive described below provides a sugar based solution suitable for use with liquid as well as solid carbon based fuels to improve combustion burning. It may be used with or without catalysts, and as a stand alone fuel for fuel cells.